8214

• UCREFRP Catalog Number: 8214
• Author: Modde, T., D. Irving and R. Anderson.
• Title: Habitat Availability and Habitat Use of Endangered Fishes in the Yampa River during Baseflow Periods.
• USFW Year: 1997.
• USFW - Doc Type: Vernal, Utah and Grand Junction, Colorado.
• Copyright Material: NO

shallow and deep runs in the middle, and two transects across the fast riffle at the top ofthe cluster.
The length of the cluster was 1,212.7 ft, mean width 162.2 ft (106.0-280.7 ft.) and mean depths
ranged from 0.97-1.95 ft. The primary habitat types found in the cluster at 433 cfs were shallow
runs (68%) and fast riffles (27%), followed by shallow pools (5%). There were no Class I or Class
II pools. The primary habitat available to Colorado squawfish at all simulated flows (1-500 cfs)
were shallow run habitats.

Cluster 3 (rm 51.0)

This cluster was sampled on 22 and 23 August 1996 (Appendix 2, Table 3) near the Little
Snake River confluence, Yampa River. The flows on these days were 184 and 176 cfs, respectively.
Four transects were surveyed along this habitat cluster. One transect was placed across a shallow
run at the bottom (control), two across shallow runs in the middle, and two transects across shallow
runs at the top of the cluster. The length of the cluster was 1,142.5 ft, mean width 418.2 ft (181.5-
652.0 ft.) and mean depths ranged from 0.54-0.94 ft. The primary habitat type found in the cluster
at 184 cfs was shallow runs (85%), followed by shallow pools (15%). There were no Class I or
Class II pools. The primary habitat available to Colorado squawfish at all simulated flows (1-500
cfs) were shallow run habitats.

Strata 4

Cluster 1 (rm 53.5)

This cluster was sampled on 16 and 17 October 1996 (Appendix 2, Table 4) near the bottom of
Cross Mountain, Yampa River. The flows on these days were 217 and 215 cfs, respectively. Six
transects were surveyed along this habitat cluster. One transect was placed across the fast riffle at
the bottom (control), two across the shallow and deep runs in the middle, and two transects across
the fast riffle at the top of the cluster. The length of the cluster was 1,205.5 ft, mean width 254.1 ft
(197.4-260.0 ft.) and mean depths ranged from 0.61-1. 97 ft. The primary habitat type found in the
cluster at 215 cfs was shallow runs (76%), followed by shallow pools (14%), deep runs (9%) and
fast riffles (1 %). There were no Class lor Class II pools. The primary habitat available to Colorado
squawfish at all simulated flows (1-500 cfs) were shallow run habitats.

Cluster 2 (rm 54.0)

This cluster was sampled on 17 and 18 October 1996 (Appendix 2, Table 5) near the bottom of
Cross Mountain, Yampa River. The flows on these days were 215 and 238 cfs, respectively. Six
transects were surveyed along this habitat cluster. One transect was placed across the fast riffle at
the bottom (contro I), two across the shallow and deep runs in the middle, and two transects across
the fast riffle at the top of the cluster. The length of the cluster was 1,422.9 ft., mean width 200.9 ft
(179.6-240.7 f1.) and mean depths ranged from 0.86-1.25 f1. The primary habitat type found in the
cluster at 238 cfs was shallow runs (96%), followed by shallow pools (4%). There were no Class I

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